Using targeted delivery, a controlled dose of a therapeutic agent may be delivered directly to a target site, e.g., a lesion in a diseased vessel, while avoiding or minimizing exposing other healthy parts of the body to the agent. Also, thanks to a local (targeted) delivery, greater amounts of therapeutic agent may be delivered to the afflicted parts of the body. In one approach to localized delivery, a balloon catheter is used, wherein the balloon has therapeutic agent disposed on its outer surface and is expanded within a vessel to deliver the therapeutic agent to the vessel wall at the lesion site to be treated. There is still a need for improved balloon catheter devices for delivery of one or more therapeutic agents to an intravascular site.